反应详情

温度

0 °C

To a suspension of 3,5-dimethoxybenzyltriphenylphosphonium bromide (0.82 g, 2.0 mmol) in THF (10 mL) at 0° C. was added solid potassium tert-butoxide (224 mg, 2.0 mmol). The resultant red solution was stirred for 15 min at 0° C. then cooled to −78° C. Solid 53 (0.3 mg, 0.90 mmol) was added and the reaction was allowed to warm to room temperature. After 30 min 10% citric acid (50 mL) was added and the mixture was partitioned between water (50 mL) and ethyl acetate (75 mL). The organic layer was washed with water (50 mL) and brine (50 mL) then dried (MgSO4), filtered and concentrated in vacuo. The crude product was purified by flash chromatography using hexanes-ethyl acetate (7:3) to yield 55 as a slightly opaque film (25 mg, 6%) after concentration and drying under high vacuum. 1H NMR (400 MHz, DMSO-d6): δ 12.04 (b s, 1H), 7.26 (d, J=8.8 Hz, 2H), 7.25 (d, J=8.8 Hz, 2H), 6.93 (d, J=8.4 Hz, 2H), 6.91 (d, J=8.4 Hz, 2H), 6.61 (d, J=12.4 Hz, 1H), 6.53 (d, J=12.0 Hz, 1H), 6.39 (d, J=2.4 Hz, 1H), 6.36 (t, J=2.4 Hz, 1H), 4.90 (dd, J=9.2 and 4.4 Hz, 1H), 3.62 (s, 6H), 3.36 (dd, J=14.0 and 4.4 Hz, 1H), 3.11 (dd, J=14.4, 8.8 Hz, 1H).

1. temperaturethen cooled to −78° C
2. temperatureto warm to room temperature
3. customthe mixture was partitioned between water (50 mL) and ethyl acetate (75 mL)
4. washThe organic layer was washed with water (50 mL) and brine (50 mL)
5. dry with materialthen dried (MgSO4)
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customThe crude product was purified by flash chromatography